Volume 18, Issue 4 (July 1990)
JIc Data Analysis Methods with a “Negative Crack Growth” Correction Procedure
It often occurs in J-R testing that some of the initial crack extension (Δa) data points have anomalous negative values. ASTM Methods E 813-87 and E 813-81, however, do not specify any procedures for treating such data. We propose a procedure for data analysis which utilizes the negative Δa values and is consistent with ASTM E 813-87. The proposed correction procedure is illustrated using a data set for austenitic steel; also, JIc values obtained using ASTM E 813-87 are compared to those obtained from its predecessor E 813-81.